Gear cutter



sept. 12, 1933. J F, LEAHY 1,926,646

GEARQUTTE Filed March 28, 1932 3 Sheets-Sheet 1 GEAR CUTTER Filed Marh 28, 1932 .'5 Sheets-Sheet 2 rPatented Sept. `12,-,1933V Y c UNITED N. Y. r

'This invention relates gearcutting tools of the pinion type for .generating gearsby plan? ing action and it has `particular :reference to fa composite cutter in Whichrthecutting is done 5 'byseparate removable blades or bits detacliably Secured to; the cutter` body' at the faces 'of the tootbflike projections on saidbody,

One of the objects of the` invention-iste pro" vide improved, means for securing the cutter iS diSPQeQd-Lft' the base; of each. tooth, c and `by Another object is to "furnish-f :means: vfor. fastening theV cutter bladesvery rigidly in the .re-`

quired positions so that tliclgear beinggenf erated will be cut very accurately, while', Vneversary removal and replacement of parts can be V and other ends the'invention consists in the novel features and combnationsof parts j Vto' be'l'iereinafter described and claimed. V InY the `accornparelying drawings:

type gear cutter embodying `my improvements;

2 is a section on line-2 2 `oi Fig.` l; l Fig. 3 is a partial plan View of the cutter shown Figs. 4 and 5 are sections Vonlines 4 4-45 and 54,5; respectively, of` Fig. 2,;

Fig". Gis ,a partialside vieWof another cutter of somewhat modiedform; n Fig. 7 is a fragmentary plan View 5VshovvninFigr6;V` s Fig. 8 is asectiorion line 8:-3 oflFgi'l; i.

Fig. 9 isa section on line 9-9pf"Fig. 8'; Y Fig.` l()V is a section` on line -l-flO of Fig. 7;v

of actuar certain parts :shown in Fig. 7;

i Fig. 12 is a section on une 12412 or Figfil Fig. 13 is a'fragmentary side elevationgofa Y further form of cutter embodyingrny improver toothed or spur gears;` and v l' i .n 4 Fig. 14 is a seotionaonline l4-14of Fig. 1 3;

.r The cutter shown in Figs. lluto yinclusive, is a cutter of tliepinion type adapted to out helicalgears -by planing` action. Such` a cutter is particularly intended for use in Sykesgearl cut-v asfto form the teethl on the` blank` at Athe desired angle Vto theaxis.4 The cutting tool has a ring-like body 20'provided With'aucentral spindle opening: ztjandL teeth .22 formed upon its leef* .-nphery: The teeth 22ameast er etherwie '.formedinteerally with.` the. heey `r ietien ;2` and `theless, the construction is suoli thatvif one o r.I

` factory fresults in actualjVpractice.. c

Fig.` l1 is an enlarged. fragmentary View foi 1 Y 'e endftlie bolt 27 is provided with a nut Slby means 1nents,'this cutter being adaptedto forinistraight are, slightlyreducedn.dimensieiissueh W; hf

meafls- The' bedr Portion 20 andthe teeth@ 2,2

are .erefereely mederem a Steel @Stinger-fers;

111g Whieh is 'Sileienily tough and rugged" fer/.1

the purpose, althouglfi easily worked'into suiteY abler form by appropriate j't'ofols.

ly directed series of shoulders 23, oneof Whic cuttingr awaythe endslo `theteeth fa seriesyor" forwardly' elireeted--end- @ieee-24 are' formed .en theteeth.H :A cutting blade `orf-"plate v25jis.disj.

Y. posed against eachoflthe end faces Y24, With'its -base w2cv resting uporitlle shoulder 23.',The teetlir 22 are directed at the required helical angleand.

l i. Y One-end facefv ef eeeh teeth 22 ie eut.' beek te ferm en Outwari l the blades V25 vare shaped'sofas to bei alinedrggli: f y erallywith fthe teeth; although:somewhatWider- Y elifleei erzslanted-'sefas .toreivegtheyriece-seayv c 4 ClellaIlCe-.alOng the apices ofetheteeth. 5 Fig. 1 is 'a'partial front endview oi a pinion The blades V25` areV sectrrgerlagainst` thetooth facesfl Vby boltsj-'I andQS, and' these` boltsare VVfarther from the-cutter axisthan are'tl'ie opposite endsgof Isaid bolts. .The bolts` 2'7` andf28,-tl1ere' fore, serve to, draw theblades. .25 against ther .surf

` facesV 247m. a somewhat'. inolineddirection` With*y respecttothe axis. ofthe cutter andwith respect to the sl'ioulders'23,v and this has `given verysatis- TheboltfZ'l has anenlargernent in the form of a-,cyli'ndri'calhead 29 disposediniia counterbore Y ilat theffront facie ofV the blade l25. V.titsrear o f'wliil'itheblade `can befdrawn andzheld against itsfseat.` The nut 3l is located in -afrecess 3'2Vat A nearer the peripheryjofithe cutterthan is bolt 27, andin thisparticular instance has a threaded yfor:

through theblade.A lAt its rear end thefbolt 28 e face Witlia hexagonalsoclre't 35,Y bestshoivn in Fig. 5, forthe insertion of a suitabletool` bylrneans 125,@ frne `read tgisiocateq vvbat' above the nut 3115* 5; i On the yrear face of. `the blade 25" between `.the

thetp tpthebore fdr thebolt Z'Lisia smalltenon eeneeereveee ee eheeeeieee ee-eezehewe e viardjeridportionV vengagingathre'aded socket Y .v VBgtginblade 25; which socketextends into but not Y .l

e which the` mais 'tightly screwed into' une blade tell' eespeci .te the exis ef the eutt'er andthe jeuterisur:

H5 l marginsthereof and extending@`.d'ownward1y 1 "i held in position by the securing bolts. j The blade' ori-bit is'urged radially in an inwarddirection are formed, 'there preferably ,being one. boltV 39 for each of the blades. Eachr bolt has a head 41v in the bladeconnnunicates with thecounterbore 30, but this is not essential, andit will be observed that after vthe blade has been piace'dinv position upon its supporting shoulder 23, either the large rst be placed in position." i

' It will be observed that whilelthefront face of *bolt 27 orthe relatively smallradial bolt'39 may bktde 25 is generali perpendicular to thel axis ofl the cutter`,`the faces 24 of the teeth against which the -blades125 are clampedare neither parallel to the-front ace'of'the blade nor at right angles to the longitudinalaxis of the corresponding tooth.

In Vthe preferred iorinthe front face of each tooth is 4vlocatedatabout 80 to the longitudinal axis of the tooth. v'Iliisfeaturefis shown particularly in Fig.:,4, and it has been found very helpful in preventingfrelative dislocation between the blade 4and its-*supporting tooth. v I! do not limit myself vto the 80 angle above mentioned,4 butin all cases the angleof the rear `face of the cutter blade to Lthe longitudinal axis 'of thetoothshould be jsubture 'of considerable advantageqinl causing YtheY v blade tobeirrnly held in the anglebetween--the y front face ofthe-toothand the" outwardly directed face ci theshoulderr y y .l The cutter shown vin Figs. 6Y to; 1.2, inclusive, is another cutter intendedfor use in 'cutting helical gears,` dii'ering somewhat detail from ithe *Y one iirst described. Here again, howeventhe in` plan thewe'dgesare tapered, being somewhat wider at :therear thanV atv the ront,as"shown inner and outerY bolts `44 and 45`i`or' securingthe Vcutter bit or bladeV 46'in place aref'located `at a slight angle to theY longitudinal axisv of the cutter v and adapted to draw Athe lcutting blade into its seat in' substantially the same Amanner;fhereinbefore described; kIn this case, however, it will be observed thatthe bit 'cons'iderably 4overlfiangs thesupporting ledge 47on' t he cutter body.v In

form'the bolt 44 is similar tothe b'ol't ZTherein-v before described, but in this case-the Youter bolt, 45, is similar to the inner bolt in that 'it' has a cylindrical head located Y in a gcounterbore in the bitand inasmuch as itis provided at the rear 'ends' witlra nut'engaging, threads ion lthe bolt shank 4so thatj when the nut is `screwed 'up'Y on the shankthe bit 'will be ldrawn rearwardly. In this form of the-invention the bits lare :of some,- what different s izeean'd shape` from those shown inFig..1 and are seatedupon flat seats 48. vlise-- tween the blades'or bitsare located' small wedges 49 which urgethe bits radially inwardk against thel seats 48. These .wedges engage `side Vsurfaces 50,151 on thebitsandfit fwillbe observed'that inFig. 7. These wedges are engaged [by: screws 52'- passing through the 1edge47 and'fhaving Ynicked so that` they canbe turned by a screw driver for drawing the wedges .radially inward and thereby engaging and drawing inward the side portions ofV the bits or blades'on opposite sides of,V the wedge.y by means such as a bolt 39 passing through'an overhanging ledge 40 on which the shouldersZ,

thef'cutter` blades rk54 are each secured in place by aninner bolt A55 Vand an outer bolt dgenerally similar .to the Ybolts 44 and 45y previously de-Y scribed. In this case, however', the inner bolt 55 4instead of being at an inclination to the axis of the cutter is parallel thereto so that the two boltsv55'and 56 are located vat a slight angle to eachother; In this'form'both bolts 55 and-56 haveheadsengaging bores which extend all the way through the blade, butV this is not essential inV all cases. `Inthis form the shoulders seating the blades at their inner edges all form in conjunction a single-shoulder, which single shoulder is of annular formation, the bottom of each blade for drawing' the'k cutter blade radially inward against the ledgebut'in some cases it maybe desirable "to employdevices of the general nature hereinbefore'.described for vachievingzth-is purpose. Y Variou's'changes can be'made in the detailsof thegear cutter structure without departing-from the scope of my invention as dened in the claims.

r While I have illustrated and described several embodiments of my invention it will be understood that I have not attempted to illustrate or describe all of the possible modifications.

vWhat'I-'clairn'iszv w A l. A composite gear cutter Yof the pinion type conipri'sir'iga body having 'teeth upon' itsperiphery v andunderlying xedshouldershaving. outwardly directed -face's located adjacent the end facesof .said teeth, said outwardly vdirectedfaces being substantially'parallel jtoathe cutter axis, cutting bladeshaving their inner edges seatedupon said `shoulders and extending alongside the `end faces or said teeth, and means #for securing-each cutting blade inposition comprising a bolt extending through thefcorresponding tooth and engaging thevcutting" blade to draw it against therend face oil thetooth, saidboltl being locatedat ar slight angle to thevlongitudinal-axis of the Jcutter and L having its en d remote iron'rthe'cutting blade dissite,r end-of` Vvsaid bolt.

posed 'nearer to the cutter axis than is the oppocomprising a bodyv having teeth upon its periphery and anunderlying ledge'projecting axially of the cutter :at one side thereof' andpresenting outwardly vdirected faces substantially' 'parallel to vthecutter axis for engagingthe inner edges of t cutting blades, Ycuttingblades having their inner 'edges vseated u'pf'Jn-said'facesv and having their rearA facesf'abutting" the forward faces ofr 'said ofsaid bolts-k-beingdisposed`at a slight-angle to the 'longitudinalfaxis of the lcutter and having teeth; andfnieans fdrsec'uringeacn blade in pdsitioncomprising-a plurality of boltsengaging the `blade and the corresponding tooth, at least one 'its end'portionwhichv engages-the' blade located. farther Vaway lfroin the `longitudinal cutter axis i5() ing theirV rear faces abutting the forwardfaces j inner edges of cutting blades, cutting blades havf ing their inner edges seated upon said surfacesV and having rear `faces adaptedtoV abut the for- Aery Vand an underlying` ledge projecting axially of the cutter at one side thereof and presenting outwardly directed faces for engaging the inner edges of cutting blades, `cutting blades having.-

their inner edges seated upon said vfaces and hav-` of said teeth, andmeans for securing each blade in position comprising a plurality of boltsengaging the blade andthe corresponding tooth, at least one of said bolts being disposed at a slight angle to the longitudinal axis of the 'cutter' and having its end portion which engages the blade located farther awayA from the longitudinal cut-" ter axis than is the rear end portion of saidibolt, said bolt having acylindrical headat its front end engaging `a bore extending completely j through the blade, and said bolt being provided at its rear end with a nut for drawing the bladev rearwardly into its seat.

4. YA composite gear cutter of the pinion type comprising a body having teeth upon itsv periphery andan underlying ledge projecting axially of the cutter at one side thereof and'having outwardly directed surfaces adapted toengagethe ward faces of the teeth, and a plurality of bolts for securing each of said' blades detachably in position, one of said bolts being an Vinner bolt ,andV j the other being an outer bolt, Vbothof Vsaid bolts beinginclined' slightly relatively to the axis of theV cutter and each having its reariend portion' closer .to the cutter axis than is thefront'end portion of said bolt.V

v5. A composite gear cutter of thepinion type comprising a body having teeth upon its periph'- ery, the end faces of said teeth at onesideof the -cutter being .so located that there is presented an outwardly'directed fixed shoulder at the base end faces of `said teeth'and seated at their inner' edgesl upon the outer faces of said shoulders, each blade having at arpcint spaced outwardly from the shoulder a hole extending through the bladeA n the'blade and tooth, and a second bolt spaced outwardly from the first and likewise passing l through a front-to-rear hole in the tooth and feo engaging the blade at its outer part for securingY it in position, said second bolt. being inclined vwith respect to the cutter axisY and `having its blade-engaging end farther from the cutter axis than is the rear end of said bolt.

6. A composite gear cutter of the pinion-type comprising a body having teeth upon its perphf ery, the end faces ofsaid Vteeth at one side of the cutter being so located that there is presented Y an outwardly directed xed shoulder at the base of each tooth, cutting blades lying against the end faces of said teeth and seated at theirinner edges upon the outer faces of said shoulders, each bladehaving at a point spaced outwardly from` the shoulder'a hole extending through theblade h said bolts having heads received from front to rear and the corresponding tooth having a through front-to-rear holefregistering with that of vtheblade',the` hole inthe blade being f the tooth, anda second bolt spacedoutvvardly from the'nrst and likewise passing through a front-to-rear hole in the tooth, saidl second bolt having a V,threadedjforvvard end engaging,` aY threaded socket in the rearface of the blade and having at its rearend a head by means of which i rcounterbored at thefrontface of the blade, a. f

saidl bolt may be rotated .for-drawing the blade rearwardly into its seat.

7. A compositegear @cutter Vof the pinion type comprising a bodyhaving teeth `upon its periphery,

the end faces of said teethat one side of vthe cutter being so locatedthat there is presented an outwardly directed fixed shoulder at the base of each 5 j j toothc`utting blades lying against the end faces of saidteeth and seated at their inner edges upon they outer faces of said shoulders, Aeach blade havf ing at a point spaced outwardly fromthe shoulder o a hole extending through the blade from `front to rear and the correspondingtooth having-,a Y through 'front-to-rear hole registering 'with that I of the blade, the hole in the blade being counterbored at the front face ofthe blade, a fastening bolt for the blade passingfthrough the registering' holes in? the bladev and Ytooth and having ahead its Within the counterbore at the front facenf the f blade and a nut at the rear face of gthetooth,V and Va secondv bolt spaced outwardly from theiirst `and likewise passing throughafront-to-rear hole in the tooth, saidsecond b olt having a threaded ,for-

1 Ward end engaging a threaded socket inthefrear face of the blade and having at its rear end a head I of saidbolts having their rear ends nearer to the by'means of which said bolt maybe rotated for. drawingthe blade rearwardly into its seat, both Q longitudinal axis of the cutter than are their front Y. blade-engaging ends.l

of each tooth, cutting `blades lying against the f 8.fA composite gear `cutter of the` pinion type" comprising abodylhaving teeth uponfits periphery, and an axially projecting ledgefat 'one side 1 presenting surfaces to engage the inner cdges'of` cutting bladescutting blades having their inner,4

edges Yseated upon said surfaces andV extending alongside the end faces of said teeth, a bolt ex- 'l tending substantially lengthwise ofthe tooth for A- Y drawing each cutting blade rearwardly-into its seat, and a bolt extending radially through the ledge and engaging a threaded socket in each bladefor urgingv theblade radially inward. I

9. In'a gear cutter of the pinion type, a body having teeth uponits'peripherm'theend face of i each of said teeth'beingspaced from the side of y an axially projecting ledge on the body onwhich said shoulders are disposed, cutting blades in the i form of gear teeth seated directly on'said shoul;v

end faces of the teeth, andrmeansU-comprising radially directed bolts engaging the cutting blades ders, means for drawingsaid bladesagainst the for urging' themradiallyinward againstvsaidl engagedby thethreadedshanks'of said bolts, and

in recessesin theV 1 4 shoulders, said blades'havingthreaded sockets "v i 

